Insulation resistance detection circuit, detection method and device thereof

Abstract

The application provides an insulation resistance detection circuit and a detection method and device thereof. The insulation resistance detection circuit comprises a control unit, an upper bridge arm, a lower bridge arm and a switching bridge. The upper bridge arm is connected between a positive electrode of a to-be-detected circuit and a ground wire. The lower bridge arm is connected between a negative electrode of the to-be-detected circuit and the ground wire. The upper bridge arm comprises a first resistor. The lower bridge arm comprises a second resistor. The first resistor and the second resistor have the same resistance value. The switching bridge comprises a resistor unit and a switching unit. The resistor unit is provided with a sampling point for being connected with a sampling circuit. The switching unit comprises a first switch and a second switch. The control unit is used for controlling the first switch and the second switch in the switching unit, so that the resistor unit is connected in parallel with the upper bridge arm or the lower bridge arm. The sampling circuit is used for sampling a first voltage when the resistor unit is connected in parallel with the upper bridge arm, and sampling a second voltage when the resistor unit is connected in parallel with the lower bridge arm. The control unit is further used for determining an insulation resistance of the to-be-detected circuit according to the first voltage and the second voltage.

Description

TECHNICAL FIELD

[0001] The present application relates to the circuit technology field, in particular to an insulation resistance detection circuit and a detection method and device thereof. BACKGROUND

[0002] In the working process of the circuit, when the circuit fails or encounters an extreme working environment, the energy storage system of the circuit will increase the probability of electric leakage, which seriously threatens the stability and reliability of the entire circuit. Therefore, it is very important to detect the insulation of the circuit for the safety of the equipment and personnel.

[0003] At present, the commonly used insulation detection device is mostly an external resistance switching method. Although this method is simple and effective, it is not suitable for real-time monitoring of the circuit, and it will reduce the insulation resistance performance when detecting the insulation resistance state. SUMMARY

[0004] Therefore, the embodiments of the present application provide an insulation resistance detection circuit and a detection method and device thereof, which can perform real-time insulation detection on the circuit without affecting the insulation resistance performance of the circuit.

[0005] The technical scheme of the embodiments of the present application is as follows:

[0006] The embodiments of the present application provide an insulation resistance detection circuit, which comprises a control unit, an upper bridge arm, a lower bridge arm and a switching bridge. The upper bridge arm is connected between the positive electrode of a to-be-detected circuit and a ground wire, the lower bridge arm is connected between the negative electrode of the to-be-detected circuit and the ground wire, the upper bridge arm comprises a first resistor, the lower bridge arm comprises a second resistor, and the resistance values of the first resistor and the second resistor are the same. The switching bridge comprises a resistor unit and a switching unit, and a sampling point for connecting with a sampling circuit is arranged in the resistor unit. Wherein,

[0007] The switching unit comprises a first switch and a second switch, the first switch and the second switch are connected in series between the positive electrode and the negative electrode of the to-be-detected circuit, and the resistor unit is connected between the ground wire and the connection line of the first switch and the second switch.

[0008] The control unit is configured to control the opening or closing of the first switch and the second switch in the switching unit, so that the resistor unit is connected in parallel with the upper bridge arm or the lower bridge arm.

[0009] The sampling circuit is configured to sample a first voltage of the sampling point when the resistor unit is connected in parallel with the upper bridge arm, and sample a second voltage of the sampling point when the resistor unit is connected in parallel with the lower bridge arm.

[0010] The control unit is further configured to determine the insulation resistance of the to-be-detected circuit according to the first voltage and the second voltage.

[0011] In the above solution, the resistance unit comprises a first resistance unit and a second resistance unit in parallel, the first resistance unit comprises a third resistance and a third switch in series, the first voltage comprises a first sub-voltage and a second sub-voltage, and the second voltage comprises a third sub-voltage and a fourth sub-voltage;

[0012] The control unit is further configured to control the opening or closing of the third switch.

[0013] The sampling circuit is further configured to sample a first sub-voltage of the sampling point when the resistance unit is connected in parallel with the upper bridge arm and the third switch is closed, sample a second sub-voltage of the sampling point when the resistance unit is connected in parallel with the upper bridge arm and the third switch is opened, sample a third sub-voltage of the sampling point when the resistance unit is connected in parallel with the lower bridge arm and the third switch is closed, and sample a fourth sub-voltage of the sampling point when the resistance unit is connected in parallel with the lower bridge arm and the third switch is opened.

[0014] The second resistance unit comprises a fourth resistance and a fifth resistance in series, and the sampling point is arranged on a connection line of the second resistance and the third resistance.

[0015] In the above solution, a fourth switch is further connected in series between the resistance unit and a connection line of the first switch and the second switch.

[0016] The control unit is further configured to control the closing or opening of the fourth switch.

[0017] In the above solution, the upper bridge arm further comprises a fifth switch connected in series with the first resistance, and the lower bridge arm further comprises a sixth switch connected in series with the second resistance.

[0018] The control unit is further configured to control the closing or opening of the fifth switch and the sixth switch.

[0019] Embodiments of the present application provide a detection method based on the insulation resistance detection circuit provided by the embodiments of the present application, comprising:

[0020] The control switching unit is controlled to connect the resistance unit in parallel with the upper bridge arm, and the sampling circuit is controlled to sample the sampling point to obtain a first voltage.

[0021] The control switching unit is controlled to connect the resistance unit in parallel with the lower bridge arm, and the sampling circuit is controlled to sample the sampling point to obtain a second voltage.

[0022] The insulation resistance of the to-be-detected circuit is determined according to the first voltage and the second voltage.

[0023] In the above solution, the control switching unit connects the resistance unit in parallel with the upper bridge arm, comprising:

[0024] The first switch of the control switching unit is closed and the second switch is opened, so that the resistance unit is connected in parallel with the upper bridge arm;

[0025] The control switching unit connecting the resistance unit in parallel with the lower bridge arm comprises:

[0026] The first switch of the control switching unit is opened and the second switch is closed, so that the resistance unit is connected in parallel with the lower bridge arm.

[0027] In the above scheme, after the control switching unit connects the resistance unit in parallel with the upper bridge arm, the sampling circuit is controlled to sample the sampling point to obtain a first voltage, comprising:

[0028] When the first to sixth switches are all opened, the fifth switch and the sixth switch are closed, and the fourth switch is closed after a first time delay;

[0029] After the fourth switch is closed, the first switch and the third switch are closed after a second time delay;

[0030] After a third time delay, the sampling circuit is controlled to sample the sampling point to obtain a first sub-voltage;

[0031] After a fourth time delay, the third switch is opened;

[0032] After a fifth time delay, the sampling circuit is controlled to sample the sampling point to obtain a second sub-voltage.

[0033] In the above scheme, after the control switching unit connects the resistance unit in parallel with the lower bridge arm, the sampling circuit is controlled to sample the sampling point to obtain a second voltage, comprising:

[0034] After a sixth time delay, the first switch is opened;

[0035] After a seventh time delay, the second switch and the third switch are closed;

[0036] After an eighth time delay, the sampling circuit is controlled to sample the sampling point to obtain a third sub-voltage;

[0037] After a ninth time delay, the third switch is opened;

[0038] After a tenth time delay, the sampling circuit is controlled to sample the sampling point to obtain a fourth sub-voltage.

[0039] In the above scheme, the insulation resistance of the to-be-tested circuit is determined according to the first voltage and the second voltage, comprising:

[0040] According to the value of the third resistor in the resistance unit, the power supply voltage of the to-be-tested circuit, the first voltage and the second voltage, a first insulation resistance between the positive electrode and the ground wire of the to-be-tested circuit and a second insulation resistance between the negative electrode and the ground wire are calculated.

[0041] The embodiment of the present application provides a detection device based on the insulation resistance detection circuit, which comprises:

[0042] The first control module is configured to control the switching unit to connect the resistance unit in parallel with the upper bridge arm, and then control the sampling circuit to sample the sampling point to obtain the first voltage.

[0043] The second control module is configured to control the switching unit to connect the resistance unit in parallel with the lower bridge arm, and then control the sampling circuit to sample the sampling point to obtain the second voltage.

[0044] The determination module is configured to determine the insulation resistance of the to-be-tested circuit according to the first voltage and the second voltage.

[0045] The embodiment of the present application provides an electronic device, which comprises:

[0046] The memory is configured to store executable instructions.

[0047] The processor is configured to execute the executable instructions stored in the memory, and implement the detection method of the insulation resistance detection circuit.

[0048] The embodiment of the present application provides a computer readable storage medium, which stores executable instructions, and is configured to cause the processor to execute the detection method of the insulation resistance detection circuit.

[0049] The embodiment of the present application provides a computer program product, which stores a computer program, and is configured to be executed by the processor to implement the detection method of the insulation resistance detection circuit.

[0050] The embodiment of the present application balances the bridge (including the upper bridge arm and the lower bridge arm) and the switching bridge to detect the insulation resistance of the to-be-tested circuit. The first switch and the second switch are controlled in cooperation to switch the resistance unit between being connected in parallel with the upper bridge arm and being connected in parallel with the lower bridge arm, so that the first voltage and the second voltage obtained by sampling in the two connection modes are used to determine the insulation resistance of the to-be-tested circuit. The detection method does not affect the path of the to-be-tested circuit, can effectively reduce the interference factors such as voltage difference and voltage fluctuation, does not affect the insulation resistance of the to-be-tested circuit, can detect two-pole grounding and multi-point grounding faults, has high speed and high accuracy, and realizes real-time insulation detection of the circuit without affecting the insulation resistance performance of the circuit. BRIEF DESCRIPTION OF DRAWINGS

[0051] In the drawings, which are not necessarily drawn to scale, like numerals can describe similar components in different views. Like numerals having different letter suffixes can represent different instances of the components. The drawings illustrate generally, by way of example, but not by way of limitation, various embodiments discussed in the present document.

[0052] Figure 1 is an optional structural schematic diagram of the insulation resistance detection circuit provided by an embodiment of the present application;

[0053] Figure 2 is an optional structural schematic diagram of the insulation resistance detection circuit provided by an embodiment of the present application;

[0054] Figure 3 is an optional structural schematic diagram of the insulation resistance detection circuit provided by an embodiment of the present application;

[0055] Figure 4 is an optional structural schematic diagram of the insulation resistance detection circuit provided by an embodiment of the present application;

[0056] Figure 5 is an optional structural schematic diagram of the electronic device 500 provided by an embodiment of the present application;

[0057] Figure 6 is an optional flow schematic diagram of the detection method of the insulation resistance detection circuit provided by an embodiment of the present application. DETAILED DESCRIPTION

[0058] In order to make the purposes, technical solutions and advantages of the present application clearer, the following will combine the drawings to further describe the present application in detail, and the described embodiments should not be regarded as limiting the present application, and all other embodiments obtained by the person of ordinary skill in the art without making creative efforts are within the scope of protection of the present application.

[0059] In the following description, "some embodiments" are related to a subset of all possible embodiments, but it can be understood that "some embodiments" can be the same subset or different subset of all possible embodiments, and can be combined with each other without conflict.

[0060] In the following description, the terms "first\second\third" are only to distinguish similar objects, and do not represent a specific order of the objects, and it can be understood that "first\second\third" can be interchanged in a specific order or sequence as allowed, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description herein is for describing the embodiments of the application only and is not intended to be limiting of the application.

[0062] The embodiments of the present application provide an insulation resistance detection circuit and a detection method and device thereof, which can perform real-time insulation detection on a circuit without affecting the insulation resistance performance of the circuit.

[0063] Firstly, the insulation resistance detection circuit provided by the embodiments of the present application is described. Referring to Figure 1 , Figure 1 is an optional structural schematic diagram of the insulation resistance detection circuit provided by the embodiments of the present application. The insulation resistance detection circuit 100 comprises a control unit (not shown in the figure), an upper bridge arm 101, a lower bridge arm 102 and a switching bridge 103. The upper bridge arm 101 is connected between the positive pole of a to-be-detected circuit 110 and a ground wire PE, the lower bridge arm 102 is connected between the negative pole of the to-be-detected circuit 110 and the ground wire PE, the upper bridge arm 101 comprises a first resistor R1, the lower bridge arm 102 comprises a second resistor R2, and the first resistor R1 and the second resistor R2 have the same resistance value. The switching bridge 103 comprises a resistor unit 1031 and a switching unit 1032. The resistor unit 1031 is provided with a sampling point for connecting a sampling circuit (not shown in the figure). The switching unit 1032 comprises a first switch K1 and a second switch K2, which are connected in series between the positive pole and the negative pole of the to-be-detected circuit 110. The resistor unit 1031 is connected between the ground wire PE and the connection line of the first switch K1 and the second switch K2. The control unit is used to control the opening or closing of the first switch K1 and the second switch K2 of the switching unit 1032, so as to make the resistor unit 1031 parallel to the upper bridge arm 101 or parallel to the lower bridge arm 102. The sampling circuit is used to sample a first voltage of the sampling point when the resistor unit 1031 is parallel to the upper bridge arm 101, and sample a second voltage of the sampling point when the resistor unit 1031 is parallel to the lower bridge arm 102. The control unit is further used to determine the insulation resistance of the to-be-detected circuit 110 according to the first voltage and the second voltage.

[0064] In the embodiments of the present application, the positive pole of the to-be-detected circuit 110 can be the positive pole of the power supply in the to-be-detected circuit 110, and the negative pole of the to-be-detected circuit 110 can be the negative pole of the power supply. In an embodiment, the to-be-detected circuit 110 can be a self-consistent energy intelligent router, which comprises a lithium battery. In this case, the positive pole of the to-be-detected circuit 110 is the positive pole of the lithium battery, and the negative pole of the to-be-detected circuit 110 is the negative pole of the lithium battery. The insulation resistance of the to-be-detected circuit 110 comprises a first insulation resistance Rp and a second insulation resistance R between the negative electrode and the ground wire PE n .

[0065] In the embodiment of the present application, the upper bridge arm 101 includes a first resistor R1 (not shown in the figure), and the lower bridge arm 102 includes a second resistor R2 (not shown in the figure), and the first resistor R1 and the second resistor R2 have the same resistance value. By using the resistors R1 and R2 with the same resistance value, the large fluctuation of the bus voltage caused by the switching of the switch in the insulation resistance detection circuit 100 can be avoided, and the charging and discharging time of the parasitic capacitance and the safety capacitance can be effectively reduced. In actual implementation, the resistor unit 1031 is provided with a sampling point for connecting with a sampling circuit. Here, the sampling device can be an analog-to-digital converter (ADC). The ADC samples the voltage of the sampling point of the to-be-tested circuit 110 through the sampling circuit to obtain a sampling voltage.

[0066] In actual implementation, the first switch K1 and the second switch K2 can be MOS tubes. In actual scenarios, the selection of the switch in the circuit needs to consider the insulation withstand voltage capacity, and the selection of the resistor mainly considers the accuracy, power and withstand voltage capacity. The control unit can control the opening or closing of the first switch K1 in the switching unit 1032, and control the opening or closing of the second switch K2. When the first switch K1 is controlled to be closed and the second switch K2 is controlled to be opened, the resistor unit 1031 is connected in parallel with the upper bridge arm 101, and at this time, the voltage sampling of the sampling point in the resistor unit 1031 can be performed through the sampling circuit to obtain a first voltage. When the first switch K1 is controlled to be opened and the second switch K2 is controlled to be closed, the resistor unit 1031 is connected in parallel with the lower bridge arm 102, and at this time, the voltage sampling of the sampling point in the resistor unit 1031 can be performed through the sampling circuit to obtain a second voltage. After the first voltage and the second voltage are sampled, the sampling circuit can send the first voltage and the second voltage to the control unit. The control unit can calculate the insulation resistance of the to-be-tested circuit 110 according to the first voltage and the second voltage and the resistance value of the related resistor in the resistor unit 1031. In the embodiment of the present application, the first switch K1 and the second switch K2 can be set to be mutually exclusive, so as to avoid the simultaneous closing of the first switch K1 and the second switch K2, so that the power supply of the to-be-tested circuit 110 is short-circuited.

[0067] In the embodiment of the present application, the insulation resistance of the to-be-tested circuit is detected through the balance bridge (including the upper bridge arm and the lower bridge arm) and the switching bridge. The resistance unit is switched between being connected in parallel with the upper bridge arm and being connected in parallel with the lower bridge arm through the cooperation control of the first switch and the second switch, so as to determine the insulation resistance of the to-be-tested circuit through the first voltage and the second voltage obtained by sampling in the two connection modes. The detection mode does not affect the path of the to-be-tested circuit, can effectively reduce the interference factors such as pressure difference and voltage fluctuation, and does not affect the insulation resistance of the to-be-tested circuit. Not only can the two-pole grounding and the multi-point grounding fault be detected, but also the speed is fast and the accuracy is high. Real-time insulation detection of the circuit is realized without affecting the insulation resistance performance of the circuit.

[0068] In some embodiments, referring to Figure 2 , Figure 2 is an optional structure diagram of the insulation resistance detection circuit provided by the embodiment of the present application. The resistance unit 1031 includes the first resistance unit 10311 and the second resistance unit 10312 connected in parallel. The first resistance unit 10311 includes the third resistance R3 and the third switch K3 connected in series. The first voltage includes the first sub-voltage V1 and the second sub-voltage V1'. The second voltage includes the third sub-voltage V2 and the fourth sub-voltage V2'. The control unit is further configured to control the opening or closing of the third switch K3. The sampling circuit is further configured to sample the first sub-voltage V1 of the sampling point when the resistance unit 1031 is connected in parallel with the upper bridge arm 101 and the third switch K3 is closed, sample the second sub-voltage V1' of the sampling point when the resistance unit 1031 is connected in parallel with the upper bridge arm 101 and the third switch K3 is opened, sample the third sub-voltage V2 of the sampling point when the resistance unit 1031 is connected in parallel with the lower bridge arm 102 and the third switch K3 is closed, and sample the fourth sub-voltage V2' of the sampling point when the resistance unit 1031 is connected in parallel with the lower bridge arm 102 and the third switch K3 is opened. The second resistance unit 10312 includes the fourth resistance R4 and the fifth resistance R5 connected in series. The sampling point is arranged on the connection line of the lower bridge arm 102 and the third resistance R3.

[0069] In practical implementation, the first resistor unit 10311 includes a third resistor R3 and a third switch K3 connected in series. The second resistor unit 10312 includes a fourth resistor R4 and a fifth resistor R5 connected in series. The sampling point is set on the connection line between the fourth resistor R4 and the fifth resistor R5 for ADC sampling. Here, the fourth resistor R4 and the fifth resistor R5 are voltage divider sampling resistors at the ADC front end, and their values ​​need to be determined in conjunction with the ADC's sampling voltage and the bus voltage range. In one embodiment, the bus voltage can be rated at 750V, ranging from 600V to 900V, corresponding to a total resistance value between one megaohm and tens of megaohms. In this embodiment, the resistance values ​​of the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, and the fifth resistor R5 should be appropriately selected; excessively small resistance values ​​are not sensitive to changes in insulation resistance.

[0070] In this embodiment of the application, the control unit can also control the first switch K1 to close, the third switch K3 to close, and the second switch K2 to open, so that the third resistor R3, the fourth resistor R4 and the fifth resistor R5 connected in series are connected to the first insulation resistance R. p In parallel operation, the voltage at the sampling point is sampled by the sampling circuit to obtain the first sub-voltage V1. Then, the third switch K3 is opened, and the voltage at the sampling point is sampled by the sampling circuit to obtain the second sub-voltage V1′. Next, the first switch K1 is opened, and the second switch K2 and the third switch K3 are closed, so that the third resistor R3, the fourth resistor R4 connected in series and the fifth resistor R5 are connected to the second insulation resistance R. n The voltage is sampled at the sampling points through a sampling circuit in parallel to obtain the third sub-voltage V2. Then, the third switch K3 is opened, and the voltage is sampled at the sampling points through the sampling circuit to obtain the fourth sub-voltage V2′.

[0071] In practical implementation, the first insulation resistance R is calculated based on the first sub-voltage V1, the second sub-voltage V1′, the third sub-voltage V2, and the fourth sub-voltage V2′. p and the second insulation resistance R n Specifically, the formula for calculating insulation resistance is as follows:

[0072]

[0073] Among them, R′ p and R′ n For R p and R n The value of R3 after parallel connection. That is, R′ p =(R p R3) / (R p +R3), R′ n =(R n R3) / (R n +R3).

[0074] According to the above formula (1), R p and R n values can be calculated, so as to obtain the insulation resistance of the circuit to be measured.

[0075] In some embodiments, referring to Figure 3 , Figure 3 is an optional structure schematic diagram of the insulation resistance detection circuit provided by the embodiments of the present application. The resistor unit 1031 is further connected in series with the connection line between the first switch K1 and the second switch K2, and the control unit is further configured to control the closing or opening of the fourth switch K4.

[0076] Here, the fourth switch K4 can be a MOS tube. In actual implementation, the fourth switch K4 connected in series between the resistor unit 1031 and the connection line between the first switch K1 and the second switch K2 can facilitate the circuit delay, and can facilitate the disconnection of the resistor unit 1031 and the circuit, thereby avoiding the damage to the sampling circuit.

[0077] In some embodiments, referring to Figure 4 , Figure 4 is an optional structure schematic diagram of the insulation resistance detection circuit provided by the embodiments of the present application. The upper bridge arm 101 further includes a fifth switch K5 connected in series with the first resistor R1, and the lower bridge arm 102 further includes a sixth switch K6 connected in series with the second resistor R2; the control unit is further configured to control the closing or opening of the fifth switch K5 and the sixth switch K6.

[0078] Here, the fifth switch K5 and the sixth switch K6 can also be MOS tubes. In actual implementation, the control unit can control the opening and closing of the fifth switch K5 and the sixth switch K6 to control the opening and closing of the upper bridge arm 101 or the lower bridge arm 102 and the circuit, thereby effectively protecting the circuit.

[0079] The electronic device provided by the embodiments of the present application for implementing the above-mentioned insulation resistance detection circuit detection method is described below.

[0080] Referring to Figure 5 , Figure 5 is an optional structure schematic diagram of the electronic device 500 provided by the embodiments of the present application, and in the embodiments of the present application, the electronic device 100 is the control unit in the insulation resistance detection circuit 100. In actual application, the electronic device 100 can be implemented as a microcontroller. Figure 5The electronic device 500 shown includes at least one processor 501 and a memory 502. The various components in the electronic device 500 are coupled together by a bus system 503. It is understood that the bus system 503 is used for implementing connection communication between the components. The bus system 503 includes, in addition to a data bus, a power bus, a control bus, and a state signal bus. However, for the sake of clarity, only the bus system 503 is marked in the figure. Figure 5

[0081] The processor 501 can be an integrated circuit chip with processing capability, such as a general purpose processor, a digital signal processor (DSP), or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, etc., which has the processing capability of signals.

[0082] The memory 502 can be removable, non-removable, or a combination thereof. Exemplary hardware devices include solid-state memory, hard disk drive, optical disk drive, etc. The memory 502 can optionally include one or more storage devices physically located away from the processor 501.

[0083] The memory 502 includes volatile memory or non-volatile memory, and can also include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), and the volatile memory can be random access memory (RAM). The memory 502 described in the embodiments of the present application is intended to include any suitable type of memory.

[0084] In some embodiments, the memory 502 is capable of storing data to support various operations, examples of which include programs, modules, and data structures or subsets or supersets thereof. In the embodiments of the present application, the memory 502 stores an operating system 5021 and a detection device based on the insulation resistance detection circuit 5022. Specifically,

[0085] The operating system 5021 includes system programs for processing various basic system services and performing hardware-related tasks, such as framework layer, core library layer, driver layer, etc., for implementing various basic services and processing hardware-based tasks.

[0086] In some embodiments, the detection device based on the insulation resistance detection circuit provided in the embodiments of the present application can be implemented in software, Figure 5 ​The insulation resistance detection circuit-based detection apparatus 5022 stored in the memory 502 is shown, which can be software in the form of programs and plug-ins, etc., including the following software modules: a first control module 50221, a second control module 50222, and a determination module 50223, which are logical, and thus can be combined or further split according to the implemented functions. The functions of the modules will be described below.

[0087] In some other embodiments, the insulation resistance detection circuit-based detection apparatus provided by the embodiments of the present application can be implemented in a hardware manner. As an example, the insulation resistance detection circuit-based detection apparatus provided by the embodiments of the present application can be a processor in the form of a hardware decoding processor, which is programmed to execute the insulation resistance detection circuit-based detection method provided by the embodiments of the present application. For example, the processor in the form of a hardware decoding processor can use one or more application-specific integrated circuits (ASICs), DSPs, programmable logic devices (PLDs), complex programmable logic devices (CPLDs), field-programmable gate arrays (FPGAs), or other electronic elements.

[0088] The insulation resistance detection circuit-based detection method provided by the embodiments of the present application will be described below in combination with an exemplary application and implementation of the control unit provided by the embodiments of the present application.

[0089] Referring to Figure 6 , Figure 6 is an optional flowchart of the insulation resistance detection circuit-based detection method provided by the embodiments of the present application, which will be described in combination with the steps shown in Figure 6 .

[0090] In step 601, after the control switching unit is controlled to connect the resistance unit in parallel with the upper bridge arm, the sampling circuit is controlled to sample the sampling point to obtain a first voltage.

[0091] In step 602, after the control switching unit is controlled to connect the resistance unit in parallel with the lower bridge arm, the sampling circuit is controlled to sample the sampling point to obtain a second voltage.

[0092] In step 603, the insulation resistance of the to-be-tested circuit is determined according to the first voltage and the second voltage.

[0093] In actual implementation, the control unit first controls the switching unit to connect the resistance unit in parallel with the upper bridge arm, and then sends a sampling control instruction to the sampling circuit to make the sampling circuit sample the sampling point to obtain a first voltage. Then, the control unit controls the switching unit to connect the resistance unit in parallel with the lower bridge arm, and controls the sampling circuit to sample the sampling point to obtain a second voltage. Then, the control unit calculates the insulation resistance of the to-be-tested circuit according to the first voltage and the second voltage.

[0094] In some embodiments, after the control unit controls the switching unit to connect the resistance unit in parallel with the upper bridge arm, the control unit controls the sampling circuit to sample the sampling point to obtain a first voltage, including: when the first switch K1 to the sixth switch K6 are all disconnected, the control unit controls the fifth switch K5 and the sixth switch K6 to be closed, and delays a first time to control the fourth switch K4 to be closed; after the fourth switch K4 is closed, the control unit delays a second time to control the first switch K1 and the third switch K3 to be closed; the control unit delays a third time to control the sampling circuit to sample the sampling point to obtain a first sub-voltage V1; the control unit delays a fourth time to control the third switch K3 to be disconnected; and the control unit delays a fifth time to control the sampling circuit to sample the sampling point to obtain a second sub-voltage V1'.

[0095] In actual implementation, the control unit can control the fifth switch K5 and the sixth switch K6 to be closed to connect the first resistance R1 and the second resistance R2 to the circuit when the first switch K1 to the sixth switch K6 are all disconnected. Then, the control unit delays a first time to control the fourth switch K4 to be closed. Here, the first time is, for example, 5 ms. Then, after the fourth switch K4 is closed, the control unit delays a second time to control the first switch K1 and the third switch K3 to be closed to connect the resistance unit in parallel with the first insulation resistance. Here, the second time is, for example, 5 ms. Then, the control unit delays a third time to control the sampling circuit to sample the sampling point to obtain a first sub-voltage V1. Here, the third time is, for example, 1500 ms. After the first sub-voltage V1 is obtained, the control unit delays a fourth time to control the third switch K3 to be disconnected to disconnect the third resistance R3 from the circuit, and delays a fifth time to control the sampling circuit to sample the sampling point to obtain a second sub-voltage V1'. Here, the fourth time is, for example, 5 ms, and the fifth time is, for example, 1500 ms. The embodiment of the present application can orderly control the circuit by delaying the closing of the switches, avoid the successful conversion of the connection of the circuit, and can sample the circuit voltage after the voltage is stable, so that the sampled first voltage is more accurate.

[0096] In some embodiments, after the control switching unit controls the resistance unit to be connected in parallel with the lower bridge arm, the control sampling circuit samples the sampling point to obtain the second voltage, including: delaying for a sixth time, controlling the first switch K1 to be opened; delaying for a seventh time, controlling the second switch K2 and the third switch K3 to be closed; delaying for an eighth time, controlling the sampling circuit to sample the sampling point to obtain a third sub voltage V2; delaying for a ninth time, controlling the third switch K3 to be opened; and delaying for a tenth time, controlling the sampling circuit to sample the sampling point to obtain a fourth sub voltage V2'.

[0097] In actual implementation, the first switch K1 is opened by delaying for the sixth time, so that the resistance unit is disconnected from the parallel connection with the first insulation resistance. Then, the second switch K2 and the third switch K3 are closed by delaying for the seventh time, so that the resistance unit is connected in parallel with the second insulation resistance. Here, the sixth time and the seventh time can both be 5 ms. Next, the sampling circuit samples the sampling point by delaying for the eighth time to obtain the third sub voltage V2. Here, the eighth time can be 1500 ms. Then, the third switch K3 is opened by delaying for the ninth time, so that the third resistance R3 is disconnected from the circuit, and the sampling circuit samples the sampling point by delaying for the tenth time to obtain the fourth sub voltage V2'. Here, the ninth time can be 5 ms, and the tenth time can be 1500 ms. By delaying control, the sampled second voltage can be more accurate.

[0098] In some embodiments, the insulation resistance of the to-be-tested circuit is determined according to the first voltage and the second voltage, including: calculating the first insulation resistance between the positive electrode and the ground wire and the second insulation resistance between the negative electrode and the ground wire PE of the to-be-tested circuit according to the value of the third resistance R3 in the resistance unit, the power supply voltage of the to-be-tested circuit, the first voltage and the second voltage.

[0099] In actual implementation, the first insulation resistance and the second insulation resistance can be calculated by the above formula (1), which will not be described here.

[0100] The following continues to describe an exemplary structure of the detection device 5022 of the insulation resistance detection circuit provided in the embodiments of the present application as a software module. In some embodiments, as shown in FIG. 5B, the software module stored in the detection device 5022 of the insulation resistance detection circuit of the memory 502 can include: Figure 1

[0101] The first control module 50221 is configured to control the sampling circuit to sample the sampling point to obtain the first voltage after the control switching unit controls the resistance unit to be connected in parallel with the upper bridge arm.

[0102] ​The second control module 50222 is configured to control the switching unit to connect the resistance unit in parallel with the lower bridge arm, and then control the sampling circuit to sample the sampling point to obtain a second voltage.

[0103] The determining module 50223 is configured to determine insulation resistances of the to-be-tested circuit according to the first voltage and the second voltage.

[0104] In some embodiments, the first control module 50221 is further configured to control the fifth switch K5 and the sixth switch K6 to be closed when the first switch K1 to the sixth switch K6 are all disconnected, control the fourth switch K4 to be closed after a first time delay, control the first switch K1 and the third switch K3 to be closed after a second time delay after the fourth switch K4 is closed, control the sampling circuit to sample the sampling point to obtain a first sub-voltage V1 after a third time delay, control the third switch K3 to be disconnected after a fourth time delay, and control the sampling circuit to sample the sampling point to obtain a second sub-voltage V1' after a fifth time delay.

[0105] In some embodiments, the second control module 50222 is further configured to control the first switch K1 to be disconnected after a sixth time delay, control the second switch K2 and the third switch K3 to be closed after a seventh time delay, control the sampling circuit to sample the sampling point to obtain a third sub-voltage V2 after an eighth time delay, control the third switch K3 to be disconnected after a ninth time delay, and control the sampling circuit to sample the sampling point to obtain a fourth sub-voltage V2' after a tenth time delay.

[0106] In some embodiments, the determining module 50223 is further configured to calculate a first insulation resistance between a positive electrode of the to-be-tested circuit and a ground wire and a second insulation resistance between a negative electrode of the to-be-tested circuit and the ground wire PE according to a value of the third resistance R3 in the resistance unit, a power supply voltage of the to-be-tested circuit, the first voltage, and the second voltage.

[0107] It should be noted that the description of the device of the embodiments of the present application is similar to the description of the above method embodiments, has similar beneficial effects to the method embodiments, and thus is not described herein.

[0108] The embodiments of the present application provide a computer program product, which includes computer instructions stored in a computer readable storage medium. A processor of a computer device reads the computer instructions from the computer readable storage medium, and the processor executes the computer instructions to enable the computer device to perform the detection method of the insulation resistance detection circuit provided in the embodiments of the present application.

[0109] The embodiment of the present application provides a computer readable storage medium storing executable instructions, wherein the executable instructions are stored, and when the executable instructions are executed by a processor, the processor executes a detection method of an insulation resistance detection circuit provided by the embodiment of the present application.

[0110] In some embodiments, the computer readable storage medium can be FRAM, ROM, PROM, EPROM, EEPROM, flash memory, magnetic surface memory, optical disc, or CD-ROM memory, and the like; and can also be various devices including one or any combination of the above storage medium.

[0111] In some embodiments, the executable instructions can be in the form of programs, software, software modules, scripts or codes, written in any form of programming language (including compiled or interpreted languages, or declarative or procedural languages), and can be deployed in any form, including being deployed as independent programs or being deployed as modules, components, subroutines or other units suitable for use in a computing environment.

[0112] As an example, the executable instructions can but not necessarily correspond to files in a file system, can be stored in part of a file storing other programs or data, for example, stored in one or more scripts in a HyperText Markup Language (HTML) document, stored in a single file dedicated to the program in question, or stored in multiple cooperative files (for example, files storing one or more modules, subroutines or code portions).

[0113] As an example, the executable instructions can be deployed to execute on one computing device, or on multiple computing devices located at one site, or on multiple computing devices distributed at multiple sites and interconnected through a communication network.

[0114] In summary, through the embodiment of the present application, real-time insulation detection of a circuit can be performed without affecting the insulation resistance performance of the circuit.

[0115] The above merely describes the embodiments of the present application, but is not used to limit the protection scope of the present application. Any modification, equivalent replacement and improvement made within the spirit and scope of the present application shall be included in the protection scope of the present application.

Claims

1. An insulation resistance detection circuit characterized by comprising: The application relates to a circuit for measuring insulation resistance of a to-be-measured circuit. The circuit comprises a control unit, an upper bridge arm, a lower bridge arm and a switching bridge, the upper bridge arm is connected between a positive electrode of the to-be-measured circuit and a ground wire, the lower bridge arm is connected between a negative electrode of the to-be-measured circuit and the ground wire, the upper bridge arm comprises a first resistor, the lower bridge arm comprises a second resistor, and the first resistor and the second resistor have the same resistance value; the switching bridge comprises a resistor unit and a switching unit, and a sampling point for connecting with a sampling circuit is arranged in the resistor unit; wherein, the switching unit comprises a first switch and a second switch, the first switch and the second switch are connected in series between the positive electrode and the negative electrode of the to-be-measured circuit, and the resistor unit is connected between the ground wire and a connecting line of the first switch and the second switch; the control unit is used for controlling opening or closing of the first switch and the second switch in the switching unit, so that the resistor unit is connected in parallel with the upper bridge arm or the lower bridge arm; the sampling circuit is used for sampling a first voltage of the sampling point when the resistor unit is connected in parallel with the upper bridge arm, and sampling a second voltage of the sampling point when the resistor unit is connected in parallel with the lower bridge arm; the control unit is further used for determining insulation resistance of the to-be-measured circuit according to the first voltage and the second voltage; wherein the resistor unit comprises a first resistor unit and a second resistor unit connected in parallel, the first resistor unit comprises a third resistor and a third switch connected in series, the first voltage comprises a first sub-voltage and a second sub-voltage, and the second voltage comprises a third sub-voltage and a fourth sub-voltage; the control unit is further used for controlling opening or closing of the third switch; the sampling circuit is further used for sampling the first sub-voltage of the sampling point when the resistor unit is connected in parallel with the upper bridge arm and the third switch is closed, sampling the second sub-voltage of the sampling point when the resistor unit is connected in parallel with the upper bridge arm and the third switch is opened, sampling the third sub-voltage of the sampling point when the resistor unit is connected in parallel with the lower bridge arm and the third switch is closed, and sampling the fourth sub-voltage of the sampling point when the resistor unit is connected in parallel with the lower bridge arm and the third switch is opened; the second resistor unit comprises a fourth resistor and a fifth resistor connected in series, and the sampling point is arranged on a connecting line of the second resistor and the third resistor; wherein a fourth switch is further connected in series between the resistor unit and the connecting line of the first switch and the second switch; the control unit is further used for controlling closing or opening of the fourth switch.

2. The circuit of claim 1, wherein, The upper bridge arm further comprises a fifth switch connected in series with the first resistor, and the lower bridge arm further comprises a sixth switch connected in series with the second resistor; the control unit is further used for controlling closing or opening of the fifth switch and the sixth switch.

3. A detection method based on the insulation resistance detection circuit according to claim 1 or 2, characterized by, The application further relates to a method for measuring insulation resistance of a to-be-measured circuit. The method comprises the following steps: controlling a switching unit to connect the resistor unit in parallel with the upper bridge arm, and then controlling a sampling circuit to sample a sampling point to obtain a first voltage; controlling the switching unit to connect the resistor unit in parallel with the lower bridge arm, and then controlling the sampling circuit to sample the sampling point to obtain a second voltage; determining insulation resistance of the to-be-measured circuit according to the first voltage and the second voltage.

4. The detection method according to claim 3, characterized in that, The control switching unit makes the resistance unit parallel to the upper bridge arm, comprising: The first switch of the control switching unit is closed and the second switch is opened to make the resistance unit parallel to the upper bridge arm; The control switching unit makes the resistance unit parallel to the lower bridge arm, comprising: The first switch of the control switching unit is opened and the second switch is closed to make the resistance unit parallel to the lower bridge arm.

5. The detection method according to claim 3, characterized in that, After the control switching unit makes the resistance unit parallel to the upper bridge arm, the sampling circuit is controlled to sample the sampling point to obtain the first voltage, comprising: When the first switch to the sixth switch are all opened, the fifth switch and the sixth switch are closed, and the fourth switch is closed after a first time delay; After the fourth switch is closed, the first switch and the third switch are closed after a second time delay; After a third time delay, the sampling circuit is controlled to sample the sampling point to obtain the first sub-voltage; After a fourth time delay, the third switch is opened; After a fifth time delay, the sampling circuit is controlled to sample the sampling point to obtain the second sub-voltage.

6. The detection method according to claim 5, characterized in that, After the control switching unit makes the resistance unit parallel to the lower bridge arm, the sampling circuit is controlled to sample the sampling point to obtain the second voltage, comprising: After a sixth time delay, the first switch is opened; After a seventh time delay, the second switch and the third switch are closed; After an eighth time delay, the sampling circuit is controlled to sample the sampling point to obtain the third sub-voltage; After a ninth time delay, the third switch is opened; After a tenth time delay, the sampling circuit is controlled to sample the sampling point to obtain the fourth sub-voltage.

7. The detection method according to claim 3, characterized in that, The insulation resistance of the to-be-tested circuit is determined according to the first voltage and the second voltage, comprising: The first insulation resistance between the positive electrode and the ground wire and the second insulation resistance between the negative electrode and the ground wire of the to-be-tested circuit are calculated according to the value of the third resistance in the resistance unit, the power supply voltage of the to-be-tested circuit, the first voltage and the second voltage.

8. A detection device based on the insulation resistance detection circuit according to claim 1 or 2, characterized by Comprising: The first control module is used for controlling the sampling circuit to sample the sampling point to obtain the first voltage after the control switching unit makes the resistance unit parallel to the upper bridge arm; The second control module is used for controlling the sampling circuit to sample the sampling point to obtain the second voltage after the control switching unit makes the resistance unit parallel to the lower bridge arm; The determination module is used for determining the insulation resistance of the to-be-tested circuit according to the first voltage and the second voltage.

Images